Thirty five million years ago, an enormous asteroid crashed into a remote region of Siberia. The heat from this impact fused minerals into diamonds. The 100 Km. wide Popigai crater remained unexplored until the 1970s when someone noticed it held finely compressed diamonds covered in permafrost. Two thousand miles from the nearest railway, and a decision by the Soviet government to keep it secret, patiently it waited another twenty years for the secret to be declassified.
Even then Soviet economy was weak; exploration was not practical. It wasn’t until a few years ago when the Sobolev Institute of Geology and Mineralogy began to pay attention, that the full scope of this deposit was understood. To date only .3 of a percent has been studied, and it holds an estimated 147 billion carats of industrial diamonds. We’re not talking the “Hope” diamond here. These are industrial quality, used primarily for drill bits. Extremely valuable just the same. There are likely trillions of carats within the crater.